Vacaville weather in September: Vacaville, California: normal highs, lows, rain and records for September
Vacaville in September has a normal high of 91°F and a normal low of 56°F, a daily mean of 73°F, falling from 93°F on the 1st to 87°F by the 30th. Measurable precipitation falls on 1 days in a normal September, 0.06 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 33°C and low of 13°C, 2 mm of precipitation in September.
- NOAA stationVacaville Nut Tree Airport
- Station IDUSW00093241
- Location38.38°N 121.96°W
- Elevation109 ft (33 m)
- Population103,994
- Jan 58° 38°
- Feb 63° 40°
- Mar 68° 43°
- Apr 73° 46°
- May 81° 51°
- Jun 90° 56°
- Jul 95° 59°
- Aug 94° 58°
- Sep 91° 56°
- Oct 80° 49°
- Nov 67° 42°
- Dec 58° 37°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Vacaville in September?
The normal high is 91°F and the normal low 56°F, for a daily mean of 73.1°F. September is 2.8°F cooler than August and 8.6°F warmer than October. September is the 3rd warmest month of the year in Vacaville and the 10th wettest. Across the month the normal high falls 6°F, from 93°F on September 1 to 87°F on September 30. From one year to the next September's mean temperature typically moves about 1.6°F either way (NOAA's standard deviation), so roughly two Septembers in three average between 72°F and 75°F.
Bars above: each day's normal high to low. Columns below: the chance of 0.01 inch or more of precipitation that day, on a scale of 0 to 100% (highest 6%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| September 1 | 93°F | 57°F | 1% | 1% |
| September 8 | 92°F | 57°F | 2% | 1% |
| September 15 | 91°F | 56°F | 3% | 1% |
| September 22 | 89°F | 55°F | 4% | 2% |
| September 30 | 87°F | 53°F | 6% | 3% |
Every day of September: normal high, low and chance of precipitation (warmest afternoon September 1, coldest night September 30)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| September 1 | 93°F | 57°F | 1% | 1% | 13 h |
| September 2 | 93°F | 57°F | 1% | 1% | 13 h |
| September 3 | 93°F | 57°F | 2% | 1% | 13 h |
| September 4 | 93°F | 57°F | 2% | 1% | 13 h |
| September 5 | 93°F | 57°F | 2% | 1% | 12 h 50 min |
| September 6 | 93°F | 57°F | 2% | 1% | 12 h 50 min |
| September 7 | 93°F | 57°F | 2% | 1% | 12 h 50 min |
| September 8 | 92°F | 57°F | 2% | 1% | 12 h 50 min |
| September 9 | 92°F | 57°F | 2% | 1% | 12 h 40 min |
| September 10 | 92°F | 57°F | 2% | 1% | 12 h 40 min |
| September 11 | 92°F | 56°F | 2% | 1% | 12 h 40 min |
| September 12 | 92°F | 56°F | 3% | 1% | 12 h 40 min |
| September 13 | 92°F | 56°F | 3% | 1% | 12 h 30 min |
| September 14 | 91°F | 56°F | 3% | 1% | 12 h 30 min |
| September 15 | 91°F | 56°F | 3% | 1% | 12 h 30 min |
| September 16 | 91°F | 56°F | 3% | 1% | 12 h 30 min |
| September 17 | 91°F | 56°F | 3% | 1% | 12 h 20 min |
| September 18 | 90°F | 56°F | 3% | 2% | 12 h 20 min |
| September 19 | 90°F | 55°F | 4% | 2% | 12 h 20 min |
| September 20 | 90°F | 55°F | 4% | 2% | 12 h 20 min |
| September 21 | 90°F | 55°F | 4% | 2% | 12 h 20 min |
| September 22 | 89°F | 55°F | 4% | 2% | 12 h 10 min |
| September 23 | 89°F | 55°F | 4% | 2% | 12 h 10 min |
| September 24 | 89°F | 54°F | 4% | 2% | 12 h 10 min |
| September 25 | 88°F | 54°F | 5% | 2% | 12 h 10 min |
| September 26 | 88°F | 54°F | 5% | 2% | 12 h |
| September 27 | 88°F | 54°F | 5% | 3% | 12 h |
| September 28 | 87°F | 54°F | 5% | 3% | 12 h |
| September 29 | 87°F | 53°F | 5% | 3% | 12 h |
| September 30 | 87°F | 53°F | 6% | 3% | 11 h 50 min |
- Normal high
- 91°FSeptember average
- Normal low
- 56°FSeptember average
- Precipitation
- 0.06 inmonth total
- Days with precipitation
- 10.01 inch or more
- Days at 90°F or more
- 16
- Daylight
- 13 h to 11 h 50 minSeptember 1 to September 30
- Days at 70°F or more
- 30
- Days at 80°F or more
- 26
- Sunshine
- 96%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00093241; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Vacaville in September?
On a given September day the chance of 0.01 inch or more is 3% on average, highest around September 30 (6%). In all, 0.06 in falls on 1 days of a normal September.
In a normal September in Vacaville, 16 days reach 90°F.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00093241.
What are the records for September in Vacaville?
The warmest September temperature on this station's record (since 1998) is 115°F, on September 6, 2022; the coldest is 41°F, on September 29, 2019. The wettest September brought 0.78 in (2022).
The September mean against the 1991-2020 normal of 73.1°F: 2021 73.9°F (+0.8), 2022 76.2°F (+3.1), 2023 70.4°F (−2.7), 2024 73.8°F (+0.7), 2025 74.0°F (+0.9), 2026 71.3°F (−1.8). 4 of 6 ran warmer than normal.
| September | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 73.9°F | +0.8°F | 0.05 in |
| 2022 | 76.2°F | +3.1°F | 0.78 in |
| 2023 | 70.4°F | −2.7°F | 0.13 in |
| 2024 | 73.8°F | +0.7°F | 0.00 in |
| 2025 | 74.0°F | +0.9°F | 0.10 in |
| 2026 | 71.3°F | −1.8°F | 0.00 in |
Source: records: ACIS, station USW00093241; recent months: ACIS, station USW00093241. Records and recent months use complete months only.
How does September in Vacaville compare across California?
Across the 219 places PlainClimate covers in California, September normal highs run from 64°F in Eureka to 104°F in Brawley; Vacaville's is 91°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.
Other months and places
- Vacaville in August94°F by day, 58°F at night
- Vacaville in October80°F by day, 49°F at night
- Vacaville through the yearEvery month, frost dates, records and recent years
- California in SeptemberThe statewide normal and the warmest and coolest places
- Brawley: California's warmest Septembernormal high 104°F